'Hurricane Panda' hackers used Microsoft zero-day, CrowdStrike says

One of the zero-day flaws patched by Microsoft on Tuesday had been used for some time by a group with suspected Chinese government ties that targets technology companies, CrowdStrike's chief executive said.

CEO Dmitri Alperovitch said his CrowdStrike has been battling with the group, which the company dubbed "Hurricane Panda," on a daily basis since earlier this year.

"They've been very persistent actors," Alperovitch said in a phone interview Tuesday. "We believe with confidence they're indeed tied to the Chinese government in their objectives."

Hurricane Panda has targeted technology infrastructure companies, Alperovitch said. He said he could not identify the companies, which use CrowdStrike's services.

CrowdStrike analysts often see attacks in action and work to boot the hackers from networks. It results in a fast-playing offense and defense, which Alperovitch said can lead to mistakes by the hackers seeking to keep their foothold.

"We are able to literally record every command they try and understand immediately what they're doing," he said.

For example, the analysts will often see hackers mistype commands, such as "hsotname" instead of "hostname" and "romote" for "remote," as they hastily try to maintain their access.

Hurricane Panda is noteworthy for using tightly written exploit code, "win64.exe," that allowed the group to move through network systems once a computer had been hacked. That tool would be uploaded using a webshell nicknamed "ChinaChopper" that the attackers had placed on a company's servers, Alperovitch said.

Win64.exe, which runs on 64-bit Windows systems, takes advantage of a privilege escalation vulnerability, which can allow attackers to gain administrative rights to other programs from the account of a user who doesn't have those permissions.

Microsoft patched the vulnerability, CVE-2014-4113, on Tuesday, but Hurricane Panda had been using it for a while. CrowdStrike notified Microsoft of the flaw when it discovered the attackers were using it, Alperovitch said.

If successfully exploited, the flaw allows arbitrary code to be run in kernel mode, allowing an attacker to install programs, view or change data or create new accounts with full administrator rights, according to a blog post from Symantec on Tuesday.

Privilege escalation flaws aren't rare, but it is uncommon to see one used for so long by a group, which indicates that the attackers have "knowledge about non-public exploitable security bugs, which usually means the exploit was either bought from a supplier or developed in-house," Alperovitch wrote in a post on the company's blog.

Win64.exe contained an interesting embedded string of characters, "woqunimalegebi," which translates to a Chinese swear word, Alperovitch said. The word is often misspelled in Chinese to avoid being blocked by the country's filtering equipment, and that intentional error changes the meaning of the vulgarity to "fertile grass mud horse in the Mahler Gobi Desert," according to CrowdStrike.

Alperovitch said it's hard to say why programmers insert such messages, but "perhaps they were trying to send a message to anyone that is reverse engineering the code."

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